/*
 * Seldon -- open source prediction engine
 * =======================================
 * Copyright 2011-2015 Seldon Technologies Ltd and Rummble Ltd (http://www.seldon.io/)
 *
 **********************************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at       
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ********************************************************************************************** 
*/
package io.seldon.importer.articles.dynamicextractors;

import org.apache.commons.lang3.StringUtils;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;

//@formatter:off
/*

example config:

{"attribute_detail_list":[
   {
       "name": "tags",
       "is_required": false,
       "extractor_type": "AllElementsTextListValue",
       "extractor_args": ["section[id=tags] > a"],
       "default_value": ""
   }
]}

*/
//@formatter:on

public class AllElementsTextListValueDynamicExtractor extends DynamicExtractor {

	@Override
	public String extract(AttributeDetail attributeDetail, String url, Document articleDoc) throws Exception {

		String attrib_value = null;

		if ((attributeDetail.extractor_args != null) && (attributeDetail.extractor_args.size() >= 1)) {
			String cssSelector = attributeDetail.extractor_args.get(0);
			Elements elements = articleDoc.select(cssSelector);
			if (StringUtils.isNotBlank(cssSelector)) {
				if (elements != null) {
					StringBuilder sb = new StringBuilder();
					boolean isFirstInList=true;
					for (Element e : elements) {
						String eText = e.text();
						eText = StringUtils.strip(eText);
						if(StringUtils.isBlank(eText)) continue;
						eText = eText.toLowerCase();
						if (isFirstInList) {
							isFirstInList = false;
						} else {
							sb.append(",");
						}
						sb.append(eText);
					}
					attrib_value = sb.toString();
				}
			}
		}

		return attrib_value;
	}

}
